Safety and efficacy of single-agent ibrutinib in patients with relapsed/refractory (R/R) marginal zone lymphoma (MZL): A multicenter, open-label, phase 2 study

The Safety of Bruton's Tyrosine Kinase Inhibitors in B-cell Malignancies: A Systematic Review

B-cell malignancies, most notably lymphomas, make up most of the non-Hodgkin lymphomas in the United States. There is limited randomized data comparing 1^st and 2^nd generation Bruton Tyrosine Kinase inhibitors. Our aim was to compare the safety profiles of 1^st versus 2^nd generation Bruton Tyrosine Kinase inhibitors. A systematic search was performed from database inception to January 13, 2020. Studies with Bruton Tyrosine Kinase inhibitor monotherapy for the treatment of B-cell malignancies in the adult population (> 18 years old) were utilized and the adverse events were extracted. Fifty-five studies that met the inclusion criteria were included in the systematic review with forty-one studies with 1^st generation and fourteen studies with 2^nd generation. The review included both clinical trials and retrospective studies with average time of follow-up of 2 years for the 1^st generation group and 18 months for the 2^nd generation group. We found that the incidence of cardiovascular adverse events was significantly higher in the 1^st generation group (20.8%) as compared to the 2^nd generation group (6.3%). However, there was a higher incidence of hematologic/oncologic and gastrointestinal side effects in the 2^nd generation group compared to the 1^st (62.3% compared to 39.2% and 36.9% compare to 28.9%). The number of Grade 5 cardiovascular events (death) were same in the 1^st generation group compared to the 2^nd generation. Further research is needed to develop highly selective Bruton Tyrosine Kinase inhibitors to avoid unwanted adverse events by minimizing off-targets. This article is protected by copyright. All rights reserved.